1. Technical Field
This invention relates to a multistage depressed collector (MSDC) klystron based amplifier, and more particularly to an MSDC klystron for use in ground based satellite and terrestrial communications.
2. Description of Background Art
Klystron tubes are known devices used for high power transmission of microwave signals. Klystrons are used typically in terrestrial transmission of radio frequency signals, such as for VHF or UHF transmission of radio and television signals. Klystrons also have use in uplink paths in ground to orbiting satellite systems.
There is a continuing effort to make klystron tubes more efficient as well as smaller with the same or increased output power. Heat loss, as well as power loss due to inefficient tube operation, is under continuous scrutiny. Multistage depressed collector tubes have been discussed in the prior art. U.S. Pat. No. 4,395,656, issued Jul. 26, 1983, is entitled Gyrotron Transmitting Tube. This patent discloses an R.F. transmitting tube and a multistage depressed collector to capture spent, spinning or orbiting electrons from a magnetic focusing area. It is the resonance due to the electrons in the magnetic field that determines the frequency of the output of the gyrotron tube. Marrying the MSDC technology in a high power uplink klystron tube suitable for satellite and terrestrial communications above 1 GHz, however, has been an unreached goal.